As a conventional doze-at-the-wheel alarming apparatus, methods of detecting meandering of a car, supervising the variation of the driver's eye point from an image process of camera images, detecting a variation of biological information such as the heart beat, breath or the like of the driver using electrodes, sensors or the like attached to the driver, and so forth have been proposed.
Such apparatus as described above have problems that they are expensive, that it is cumbersome for the driver to attach them, that they restrict the behavior of the driver, that they operate also when the vehicle is not running and so forth.